that's weird. how do you render the _form partial ? sometimes the variables are not available in the partials, which seems to be the case here.
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m_xDec 2 '12 at 19:49

I created new empty project as in previous(render 'form') and it is working. The porblem, that I need my old project. I tried to copy code from partial, but it doesn't work. What I need to do ? Work in new projec? But it is running from problem.
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DenMedDec 2 '12 at 19:53

There you can see if you pass nil into this method it will throw the error you posted - so check where and why @ticket gets nil
To do that you might want to follow this guide, it explains how to debug a rails app.